Wikimedia
Wikipedia: Las Cuatro Operaciones Basicas
In Spanish. encyclopedic explanations of the four basic operations. Also linked to other information on arithmetic.
Quia
Quia: Story Problems With Mixed Practice
Your problem-solving skills are put to the test in this interactive word problem game on this site. Employ a variety of mathematical skills and strategies including logical reasoning and computation. Multiple choice problems created for...
University of Cambridge
University of Cambridge: Nrich: 1, 2, 3, 4, 5
On this one page website sharpen your logic and problem solving skills while working on this challenge. The solution is available to double check your solution.
University of Waterloo (Canada)
University of Waterloo: Order of Operations
A quick game in which students must evaluate an arithmetic expression involving three numbers and any of the four basic operations (addition, subtraction, multiplication, division). Students must be careful to do the operations in the...
Khan Academy
Khan Academy: Subtracting Decimals: Thousandths
In this exercise, students practice subtracting decimals. Students receive immediate feedback and have the opportunity to get hints and try questions repeatedly.
Khan Academy
Khan Academy: Scientific Notation Challenge
Practice solving more challenging problems involving scientific notation. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video, or receive hints.
University of Cambridge
University of Cambridge: Nrich: Make 100
On this one page website sharpen your logic and problem solving skills while working on this challenge. The solution is available to double check your solution.